The Laboratory Core will support all six projects. The Assay Module will provide biochemical and immunochemical assays used to measure mineral regulating hormones and cytokines in Projects 1, 2, and 3. The second function of the Core Laboratory will be to operate a Cell Culture Module. This facility will be responsible for growth of cell lines (all projects), propagation of plasmids (Projects 1,3,4,5 and 6) and also provide nude mouse facilities for Projects 2,3,4,5 and 6. The third function of the Core will be to serve all projects as a Supply and Service Module. This unit will order and stock common supplies including radioisotopes, restriction enzymes, oligonucleotides, gases and buffers. Centralized cataloging and inventory control will improve cost- effectiveness and facilitate maximum usage of these expensive and perishable reagents. This core therefore provides essential expertise to facilitate performance of all the experiments proposed in this Program Project.